As it turns out, albeit I don’t do voice as my career focus, I decided to help out a team member and took ownership of an issue that came up. It was a phone that wasn’t working, one that was attached to an ATA 190. After I tracked down the device I typed it’s IP address into my web browser and found it in a Recovery Firmware state. What us traditional Cisco route/switch guys would consider “ROMMON” as a loose equivalent. In this case it is important to note, since the device wasn’t function on proper firmware and was in recovery mode, the IP address of the ATA is actually in the Data VLAN at this point, NOT the Voice VLAN.

This year I was unable to make it to Cisco Live U.S. for a variety of reasons. Sometimes the stars don’t align and you can’t make logistics work, or maybe financials just fall short. That doesn’t mean you can’t “go” to CLUS even if it may be remotely and in spirit. Trust me, if the spirits right it’s an exhausting week even when you aren’t there.

I dedicated a lot of effort this year into “attending” even though I was remote just shy of a couple thousand miles away. Here’s how I did it!Continue reading

Permanent link to this article: http://www.packetpilot.com/clus-2017-a-remote-view/

Say you have a network that currently has an MPLS WAN from your HQ to all of your Branches. You want to migrate these MPLS connections into a DMVPN design and in doing that, you would like to move the MPLS links into a Front Door VRF. There comes a challenge with this move in regards to the routing tables and when to move the headend.

First of all a disclaimer. I am NOT a programer. I promise this could probably be cleaned up considerably by someone that actually does programming. Also, It may require some tweaking to work on your system. This is tested on Mac 10.12.3 and SecureCRT 8.1*

I’ve always loved using SecureCRT. I often find myself needing to add anywhere from a small to a large number of sessions to my list. Especially in my current role. I had remembered in my past at an old roll where I used Windows as my primary OS (work issued) that I had discovered a forum that had a python and VBS script to import sessions out of a CSV. Now that I am running on Apple I sought out that old forum and grabbed the python script. Drats!!! The python script doesn’t work on my new version of SecureCRT for Mac (8.1). Then I started thinking. Most of the time clients give me a nice spreadsheet of IP addresses. This got me thinking, why not write my own that uses Excel. So here it is!

tl;dr – THANK YOU ALL!

Yesterday morning I opened up my Spark app and was surprised to see I was added to the Cisco Champions room. I checked my e-mail and saw nothing. I knew it was being announced soon do to some twitter chatter. After validating with members it was true. I was selected as a 2017 member of Cisco Champions. I’m going to say I’m blown away even still today. I am absolutely honored to be part of such an amazing group of individuals. It has caused me to sit back and think about how I even came to know the people I look up to. So how did it start?

The new year just sprung upon us. This is usually when I go through my bag and reorganize. I figured hey why not post what I carry. I know, it’s nothing new nor original. I’m surely not the first person to do this post. I always find it interesting though to see what others carry so maybe someone is interested in my daily carry.

So, here we go. Lets start with the top left and move through from there.

Super Glue

I always end up ripping a finger or knuckle home on something. Super glue it the go to fix

Again, haven’t had a reason to upgrade but love noise canceling when necessary

So where does it all go? It seems like a lot listed out but to be honest it barely fills up the backpack I carry. I currently carry an OGIO Renegade RSS. Plenty of room for more than you need. Also, before anyone asks “what? No box cutter?!”. Daily carry is a Gerber Paraframe of sorts on my person.

Permanent link to this article: http://www.packetpilot.com/2017-whats-in-my-bag/

I’ve always wanted to find a quick way to test a multicast deployment in a Cisco environment. Many of us are already familiar with simply pinging a multicast address from an interface, and going to another router and issuing the ip igmp join-group command.

I’ve came across a new way to test that I’ve missed over the years but has apparently been around. This tool is the Multicast Routing Monitor. It has a fairly straight forward configuration and will at least give you some view into your multicast domain and it’s functionality.

I came across a paragraph in an older book in regards to EIGRP operation. As I read it I was kind of dumfounded. To be honest I didn’t believe it at first so of course I had to lab it to see if it was true. It turns out that it is in fact the way EIGRP operates in this very specific circumstance. I had never seen it before in some of my favorite books nor through my favorite video training vendors. So my findings are this: In a very specific scenario, EIGRP will advertise static routes into EIGRP as internal routes without any redistribution statements.

This lab will cover the topics 5.5.a, 5.5.b, and 5.5.c HSRP Priority, Preemption, and Version from the Cisco Certified Network Associate (CCNA) blueprint. It will test your understanding and knowledge of configure DHCP Servers on Cisco IOS devices. Please use the initial configurations as a template for your lab utilizing whatever console means you have (GNS, Physical Gear, VIRL, etc).

In this lab we will configure the First Hop Redundancy Protocol calls Hot Standby Router Protocol (HSRP). This is a two part lab. The first part we will configure “Legacy” HSRP. In part two we will configure HSRPv2. The initial config files contain the starting configs that will be used for both labs. They set up routing and DHCP for you.

Part1:
Configure R1 Eth1/0 with address 192.168.12.3
Configure R2 Eth1/0 with address 192.168.12.2
Configure HSRP on R1 and R2 using the Virtual IP address of 192.168.12.1
Ensure PC can obtain a DHCP address and ping 3.3.3.3 with either R1 or R2 failing.

Part2:
Rebuild HSRP using group number 4000
Use Virtual IP address of 192.168.12.1
R1 should be active whenever it is online. If it is to fail and come back it should take over as the active forwarder.

Configure a DHCP scope on R3 to provide IP addresses for R2s E0/1 segment excluding R2s address and using it as a default gateway.

Configure R2 to relay DHCP requests to R3 for address lease obtainment. R1’s Ethernet 0/1 interface should be set to use DHCP.

To begin we will configure R2’s ethernet interfaces with the indicated IP addresses.

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R2(config)#int e0/1

R2(config-if)#ip addr 12.1.2.2 255.255.255.0

R2(config)#int e0/0

R2(config-if)#ip addr 23.2.3.2 255.255.255.0

Next we will configure R3’s Ethernet 0/0 interface and create the default routing towards R2.

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R3(config)#int e0/0

R3(config-if)#ip addr 23.2.3.3 255.255.255.0

R3(config-if)#no shut

R3(config)#ip route 0.0.0.0 0.0.0.0 23.2.3.2

As indicated in the directions we will exclude R2’s Ethernet 0/1 address from any created DHCP Pools and create a pool to supply addresses to the 12.1.2.0/24 subnet utilizing 12.1.2.2 as the default gateway. This configuration will be done on R3

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R3(config)#ip dhcp excluded-address 12.1.2.2

R3(config)#ip dhcp pool R2-E0-1-LAN

R3(dhcp-config)#network 12.1.2.0 255.255.255.0

R3(dhcp-config)#default-router 12.1.2.2

With this configuration in place we will debug R1 with debug DHCP detail which will enable DHCP client messages. On R3 we will debug DHCP server packets to verify it’s DHCP pool functionality. After debugs are enable we will enable the R1 Ethernet 0/1 as a DHCP client.

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R1#debug dhcp detail

R3#debug ip dhcp server packet

R1(config)#int e0/1

R1(config-if)#no shut

R1(config-if)#ip addr dhcp

I have copied the output of a single attempt from R1’s debug to obtain a DHCP lease. There is no output from R3 indicating that it never received a request for an address from a DHCP pool.

Not fix this issue we will add the necessary command for relaying DHCP requests to R2. This command is applied on the incoming interface for DHCP discovery messages. In the case of R2 it will be on the Ethernet0/1 interface.

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R2(config)#int e0/1

R2(config-if)#ip helper-address 23.2.3.3

Now that we have the helper-address in place we will bring up the R1 interface again with debugs running on all three routers.

R1’s debug is show below. We can see the router issues DHCP discover messages out it’s interface ultimately coming up with and address of 12.1.2.4 with a default gateway of 12.1.2.2.

On R2 with DHCP server debugs on we can see R2 setting the GIADDR value to the interface the DHCP Discovery came in on. This is relayed to the address listed in the helper-address configuration and is used to help identify the correct DHCP pool to pick address from.

On R3 we can see the DHCP Discover message being received and it is indicated that it came in through the relay address of R2’s interface. The DHCP server utilizing this information to select an address from a pool and send it back to the relaying router as unicast. R2 then sends it to the appropriate client and this process repeats through the DORA operation.

We can now use R1 to verify our configuration is successful. With everything in place we should see a default route achieved from the default-route command in the DHCP pool pointing to R2’s interface on Ethernet0/1. We can also ping R3’s 23.2.3.3 address.

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R1#show ip route

Codes:C-connected,S-static,R-RIP,M-mobile,B-BGP

D-EIGRP,EX-EIGRP external,O-OSPF,IA-OSPF inter area

N1-OSPF NSSA external type1,N2-OSPF NSSA external type2

E1-OSPF external type1,E2-OSPF external type2

i-IS-IS,su-IS-ISsummary,L1-IS-ISlevel-1,L2-IS-ISlevel-2

ia-IS-ISinter area,*-candidate default,U-per-user staticroute

o-ODR,P-periodic downloaded staticroute

Gateway of last resort is12.1.2.2tonetwork0.0.0.0

23.0.0.0/32issubnetted,1subnets

S23.2.3.3[254/0]via12.1.2.2,Ethernet0/1

12.0.0.0/24issubnetted,1subnets

C12.1.2.0isdirectly connected,Ethernet0/1

S*0.0.0.0/0[254/0]via12.1.2.2

R1#ping 23.2.3.3

Type escape sequence toabort.

Sending5,100-byteICMP Echos to23.2.3.3,timeout is2seconds:

!!!!!

Success rate is100percent(5/5),round-trip min/avg/max=116/125/144ms

There are no initial configurations for this topology. All you need is a blank router with two interfaces in two different LAN segments.

Permanent link to this article: http://www.packetpilot.com/ccna-dhcp-client-and-relay/